99% of the cost of this campground is because you're on Key West. Location, location, location! When I was there, and it was some time ago, it was pretty grungy and the cost seemed to be way over what I thought it was worth. Lots of trees, gazebos, and mangrove views are nice. You're definitely close to the action. I would recommend a trailer that you can un-hitch, because running around on Key West in a big Class A is going to be cumbersome. All in all, not a bad price for the experience. You're not going to find any other accommodations for any less than a pad here.
Nice park. When I went, the fireflies were in abundance at dusk. They even seemed to flicker in unison! I just missed the manatees, but plenty of other life to see in the crystal clear water. Note to tenters: Railroad nearby was pretty noisy all night long.
I am staying here as an extended stay guest. The extended stay rate is the best in the area. As of 6/2007, it is $270 per month, plus $30 for cable, plus electric and LP. Compared to other campsites I looked at making an extended stay at, the KOA offers the lowest rate, Cable TV (that you can call Comcast and get cable modem connected to at your cost), beautiful wooded sites that you can stretch out on, catch-and-eat fishing from the lake, 1 minute from I-95, and a store stocked with essential RV'ing goodies and groceries(though the prices will make you look for the closest Wal Mart). Though staff is VERY friendly, it can be a good thing to just take some matters in your own hands. This KOA has VERY few tent sites - 5 total. If you tent, PLEASE call for reservations. Pool is very clean but can be busy. I'm very happy here and have no hurries to leave.